Electrical switch gear



July 31, 1928. 1 1,678,845

w. A, coATEs ET AL ELECTRICAL SWITCH GEAR Filed June 18. 1921 3 Sheets-Sheet l i7 L8 [I7 I6 I4 I8 WITNESSES: P4 l INVENTORS Wmeizza fallita# v ATTORNEY July 31,1928. 1,678,845

` w. A. coA'rEs ET AL.

ELECTRICAL SWIlTCH GEAR 'Filed June 18, 1921 s sheets-sheet 2 WITNESSESZ INVENTORS /dmzseizz? wins ATTORNEY July 31, 1928. 1,678,845

w. A. coATr-:s Er Al. l

ELECTRICAL SWITCH GEAR Filed June 1e. 1921 s sheets-sheet s wlTNEssEs; l lNvENToRS y Miam amm www Y warmem Patented July 31, 1928.`

UNITED STATES 1,678,845 PATENT OFFICE.

WILLIAM ANsELM CoArEs, or cIIoRLroN-CUM-IIARDY, ANR DAVID'V REGINALD 'LAvIEs 0E srRErroRn, MANCHESTER, ENGLAND, AssIeNoRs To wEsTINGPIoUsE ELECTRIC a MANUFACTURING COMPANY, A CORPORATION or PENNSYLVANIA.

ELECTRICAL SWITCH GEAR.

` Application' led June 18, 1921, Serial No'. 478,575, and in Great Britain June 22, 1920.

This invention relates to electrical switch gear o what is commonly known as Vthe iron-clad type in which the various switches, conductors, instrument and other transformers which`are or may be connected between the oil switch and the bus-bars are enclosed a .I

,the ISOlatlng and selector switches are arin casings usually of metal which are afterwards filled with oil or a solidinsulating material.

Our invention has for its object to provide an improved construction of switehgear of the type described above in which the amount of oil insulation required is reduced.

According to the invention, those parts of the gear which comprise fixed joints or conductors including the metallic terminals of the isolating and selector switches are dis posed in receptacles which are filled with solid insulating material while only the receptacles containing the transformers and the usualoil switch are filled with oil. lisolating or disconnecting switches and the selector switches are of the plug type, thesocket and the head through whichv the plug is reciprocated being connected by an insulating tube preferably of micanite which may or may not be filled with oil. f

Incarrying out the invention, three "mam chambers or receptacles are provided, one consisting of a comparatively long tubular chamber extending horizontally in front .of

\ the apparatus and containing the bus-bars,

the conductors and cables being led in at` the top and bottom of this chamber, respectively.

The second receptacle is located behind the bus-ba-r chamber and contains the transformers for the instruments and for the protective gear or such of these as are provided.

The third receptacle is .the usual oil switch tank. These receptacles are connected by a casing or casings in which the connections between the transformers and the terminals of the oil switches and .isolating and selector switches are located. v

The connections are preferably made of copper conductors insulated, where they pass through the walls of the various chambers or receptacles, with micanite or other tubes, the intermediate space being filled with a bituminous insulatlng compound. Theisolating and selector switches are of the plugtype, the fixed socket portion and the head through which the movable plug or plunger is passed being connected by a tubeY pf micanite or other suitable insulating material which may or may not be filled with insulating oil. The insulating tube is preferably continued so as to enc-lose the operating rod of the switch.

In one formof the invention, the axes of ranged vertically and the socket portion of each switch is located within the chamber or receptacle containing the bus-bars.

In another form of the invention, the axes illustrate, by way of example, a constructie-n of switch gea-r in accordance with the invention as applied to a three-phase electrical .system with split conductor protection.

Fig. 1 is an electrical diagram of the cir- I cuits of one phase conductor ofthe switch gear.

Fig. 2 is a `sectional side elevation 'of one form of the switch gear with the isolating and selector switches horizontally disposed and showing the ressential elements of one phase of the system. y

Fig. 3' is a front sectional elevation of the switch gear, the right-hand portion thereof being a section on the line II-II of Fig. 2, while the left-hand portion is a section on the line III-III of Fig. 2, and

Fig. 4 is 'a view, similar to that of Fig..2, showing a modified form o-f the switch gear wherein the isolating and selector switches are vertically disposed.

Referring to the drawings, Fig. 1 clearly shows how the cables 1, having the split conductors 2, 2, areconnected by means of the main oil switch 3 with either of the two sets of bus-bars 4 and 5.- The conductors 2, 2 are each connected to a terminal 6 of the isolating switches 7 7 the other terminals 8 of which are connected in turn through the series transformer devices 9, 10 to separate blocks -pital bars 5, are arranged, as shown,*inv

3. The other terminal 12 of the oil switch is connected by a conductor 13 which divides at 14 to the terminals 15, 15 of the two .selector switches 16, 16. The other terminals 17, 17 of the switches 16, 16 are respectively connected to one of the bus-bars of each set 4 and 5 by means of the conductors 18,y so

that either set of bus-bars may be connected y to the oil switch as desired.

Referring now to Figs. 2 and 3, thev busbars' which comprise, for example, a set of main bars 4 and a set of auxiliary or hosa tubular chamber 20 which extends across the front of the switch gear and advanta e` ously comprises a number of cast or rol ed metal sections secured together and supportthe cable conductors 2 and the isolating switch terminals 6 and the connections between the selector switch terminals 17 and the bus-bars 4 and 5.

The isolating and selector switches 7 and.

16 areI advantageously of the plug. type, and in theconstruction of switch gear illustrated in Figs. y2 and 3, these switches are similar and are arranged side-by-side in substan' tially the same horizontal plane, being disfposed in a. metal casing 25 which communicates at the front with the opening 23 in the chamber 2O and extends horizontally backwards between' the latter and the oil switch A 3. e, The` said casing 25 is preferably formed of associated metal sections and extends across the Whole width of the switch gear, the phase conductors of which may be sep- I arated Iby partitions 26.

Tlie plungcrs of the isolating and selector switches 7 and 16 are connected by rods 27 of insulating materia-l, such as that known as bakelite, to the operating mechanismof the switches. This mechanism conveniently comprises screw-and-nut gear 30 from a hand-wheel or handle 31, as shown, althoughy any vother means may be provided forreciprocating the plungers of the switches 7 and 16 to and away ets 6 and 17.

To the rear end of the casing 25 are attached the head or heads 33 of the oil switch or switches 3 which are supported on girders from the terminal sock- 34, 34 forming part of the framework of thel switch gear. The contact studs 11 and 12 of each oil switch terminate in the metal casing 35 attached within the lieall 33, and the 011 tank 36 is supported beneath the head 33 by means of stays 37 and a beam 38 or in any convenient manner.

. 'The cable conductors 2, 2 of each phase separate in the chamber 20 and are connected to strip conductors 24att\ached to, and depending from, 'the isolating switch terminals 6. In similar manner, the strip conductors 18 connect the terminals 17 of the selector switches with the l bus-bars 4 and 5. l

'llhev terminals 8 and 15-of'the' isolating and selector switches constituting the bushes or heads` through which the plunger portions of the switches 7 and 16 slide are connected `by means of strip conductors 40 to metal rodfconductors 41 passing downwards in insulating bushings 42 through orifices in -the floor-of the casing 25.

The terminals 11. 12 of the oil switch 3 The rod conductors 41 .connected to the' isolating switches are connected to the series transformer devices, such, for eXample,-`as the split conductor protection transformer 9` and the instrument transformer 10 which are supported beneath the casing 25. The

transformer devices .are connected in turn with the rod conductors`46 which are connected to the studs 11, 11 of the oil switch.

The conductors 41 and 46, which are connected respectively with the terminals 15 of lthe selectorf switches 16 and the polesl 1'2 (shown only in Fig. 1 of the oil switch. are electrically connected y means of the strip conductor 13 (see Figs. 1 and 3), each pair of the selector switches being connected to a rod conductor 41 by means of a strip conductor 14.

The series transformer devices 9, 10 of each phase, together with the lower ends of the conductors 41 and 46 and the electrical connections therewith, are enclosed in a tank 48 also supportedl beneath the receptacle 25.- The isolating and selector switches 7 and 16 are encased in tubes 49 of an insulating material, such as micanite, in order v to protectl the said switches andthe operating mechanisms from the insulating com-` pound and to maintain a space in which the moving parts can operate.

A convenient position for the potential transformer, if provided, is at the front of the switch gear above the chamber 25, the cover sectiony of which, as indicated at 50, may be suitably sha ed to receive and support the tank 51 of t e said transformer which is in part shown in outline at 52 (Fig. 2). The potential transformer fuses 53 are preferably also .arranged in the tank 51 so as to be flooded with oil when the tank is illed up and an insulating barrier 54 is preferably arranged between the transformer 52 and the fuses 53.

When the various transformer devices and switches have been arranged in their proper positions and all of the permanentconnections have been made, the bus-bar chamber 20, the casing 25 containing the isolating and selector switches and the terminal casing of the oil switch 3, that is to say, those casings which contain the `permanent connections of the switch gear, includingv the' metallicterminal parts of the isolating and selector switches, are filled with insulating material or compound, the movable parts of the isolating and selector switches being protected by the tubes 49,. which surround them. The tanks 48 .are then filled with oil yto therequisite level and are secured be neath the casing 25 so that the transformer devices and the connections betweenithe conductors 41 and 46 are immersed in the oil.

Referring' to the modified form of the switch-gear shown in Fig. 4, to which similar reference numerals have been applied as far as possible, the isolating and selector switches 7 and 16 instead of being arranged horizontally in the casing 25 as in the form above described are `vertically disposed. The protecting tubes 49 extend through the opening 23 into the bus-bar chamber 2O while the upper ends of the tubes 49 and also the screw and nut mechanism 28 .and 29 are protected by a. metal casing 56.

The upper parts of the switches are surl rounded and protected by the compound in the casing 25 while the lower terminals are protected by the compound in the bus-bar` Athe sizeof the spaces which are filled with compound. vThe potential transformer tank 51 in this modification of the switchV gear is conveniently arranged midway between the chamber 20 and the oil switch 3, and as before, is supported on the top of the casing 25. The oil switch operating mechanism is indicated as a whole at 58, but as it forms no partof the present invention, it iS not described `in detail.

It will be seen that with the -switch gear arranged in accordance with the invention,

lapart from the usual oil switch tank 36 and the potential transformer tank 51, only the comparatively small tanks 48 haveito be filled with dil. Consequently, the quantity of oil necessary for the switch gear is considerably reduced below that which would be required to fill the casings containing the isolating and selector switches'and the 'vari'- ous conductors and connections fasl well as the transformerand oil switch tanks. The protecting tubes 49 of the isolating and seletor switches may, if desired, be'flled with o1 l It will be understood-that lthe switch' gear I may be modified in certain constructional ways without departlng from the scope of :the invention; for example, the bus-bar chamber`20, the casing 25 and the tanks 48 and also the potential transformer tank 36 maybe arranged in different positions' relativelIy to one another ,and'tothe oil switches 5. n

some cases the bus-bars may not be provided fin duplicate so that'certain of the i so-called selector switches are omitted, those remaining being then more properly termed isolating switches. Although-a three-phase split conductor system has been described yand shown on the drawings, it will be understood that the invention is in no way restricted to such systems but is applicable to single-phase or other systems of electrical distribution. It will also be obvious that, instead of providing a handle 31 for each of the isolating and selector switches, a common operating handle maybe provided to operate all these switches, simultaneously, suitable means being provided for rendering either the one or the other of each pair of the selector switches inoperative so that either the bus-bars `4 or the bus-bars 5 are connected.

.Ifv desired, interlocking devices may be' provided between the operating mechanisms of the oil switches land of the isolating and selector switches and certainother parts of -the switch gear such as the oil switch tanks and the lid of the potential transformer tank in order to prevent danger from incorrect operation of the switch gear.

Although three cables 1 have been shown as entering the bus-bar chamber 20, it will be understood that a single three-core split conductor cable may be in some cases used.

It will be understood, furthermore, that whereas the invention hasl been referred to as relating to ironclad switch gear, the various casings may be formed of other metal,

for instance, a non-magnetic metal when the switch gear is designed for heavy currents.

We claim as our invention:

1. Electrical switch gearL comprising a housing containin molded insulating material and an enclose switch unit substantially surrounded by the insulating material and having -conducting terminals embedded therein. A

2. Electrical switch gear comprising a housing containing molded insulating material, an enclosed switch unit substantially surrounded by said material and having conducting terminals embedded therein, and

'an electrical device disposed eXteriorly of the housing and having its terminals projecting thereinto and connected/to the said conducting terminals.

3. Electrical switch gear comprising a housing containing molded insulating material,anenclosed switch unit substantially surrounded by said material and having conducting terminals embedded therein, and an enclosed oil-immersed electrical device disposed exteriorly of the housing and having its terminals projecting thereinto and co-nnected to the said conducting terminals.

4. Electrical switch gear comprising a4 housing containing molded insulating material7 an enclosed switch unit substantially surrounded by said material and having conducting terminals embedded therein, an oilimmersed electrical device disposed exteriorly of the housing and having its terminals projecting thereinto and connected to the said conducting terminals and an enclosure for the said device attached to the i substantially integral block of molded inbedded.

7. Electrical switch gear comprising a housing for feed conductors, a dlsconneeting switch, a housing forthe disconnecting switch disposed substantially normal to the housing for the feed conductors and communicating therewith, a tank suspended beneath the housing for the disconnecting switch for containing oil and electrical apparatus and terminals projecting from the housing for the disconnecting switch into the said tank, the said housings being filled with molded insulating material for surrounding the said conductors and the disconnecting switch.

8. Electrical switch gear comprising an enclosedswitch having terminal members projecting therefrom, connectors for conductively connecting the terminal members to the feed conductors, and a housing for enclosing the enclosed switch, the connectors and the feed conductors lilled with molded insulating material whereby the enclosed elements are substantially surrounded by the material.

9, Electricalswitch gear comprising a switch, an enclosure therefor, terminals projecting from the enclosure, and a housing surrounding the'enclosure vand filled with molded insulating material in which the enclosure' and terminalsv are embedded.

10. Electrical switch gear comprising a switch, an enclosure therefor and a casing substantially surrounding the enclosure and filled with molded insulating material.

In testimony whereof, we have hereunto subcribed our names this first day cf June 192 WILLIAM ANsnLM coATns. Iinnvm REGINALD nAvms. 

